Hydrogen fuel cell vehicles (FCVs) and hydrogen internal combustion engine (ICE) vehicles both present promising opportunities for cutting carbon dioxide emissions and reducing reliance on foreign oil. Hydrogen is often viewed as a transitional technology, bridging the gap between traditional gasoline-powered vehicles and fully hydrogen-powered ones. This paper explores hydrogen technology by examining key factors such as power fuel efficiency, tank capacity, and recent technological advancements. An economic analysis is then conducted to assess the potential impacts of widespread hydrogen vehicle adoption in the United States. The viability of hydrogen vehicles hinges on several critical uncertainties, including advancements in vehicle and production technologies, fluctuations in crude oil prices, and the effectiveness of carbon dioxide emission abatement strategies. The analysis suggests that while promoting hydrogen-powered vehicles may align with long-term environmental goals, policymakers might find it more prudent to focus on encouraging gasoline-electric hybrid vehicles as a more immediate and practical strategy for reducing emissions and improving energy efficiency.